Structural highlights
Function
[GRIA4_RAT] Receptor for glutamate that functions as ligand-gated ion channel in the central nervous system and plays an important role in excitatory synaptic transmission. L-glutamate acts as an excitatory neurotransmitter at many synapses in the central nervous system. Binding of the excitatory neurotransmitter L-glutamate induces a conformation change, leading to the opening of the cation channel, and thereby converts the chemical signal to an electrical impulse. The receptor then desensitizes rapidly and enters a transient inactive state, characterized by the presence of bound agonist. In the presence of CACNG4 or CACNG7 or CACNG8, shows resensitization which is characterized by a delayed accumulation of current flux upon continued application of glutamate (By similarity).[1] [2] [3]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) class of ionotropic glutamate receptors comprises four different subunits: iGluR1/iGluR2 and iGluR3/iGluR4 forming two subgroups. Three-dimensional structures have been reported only of the ligand-binding core of iGluR2. Here, we present two X-ray structures of a soluble construct of the R/G unedited flip splice variant of the ligand-binding core of iGluR4 (iGluR4(i)(R)-S1S2) in complex with glutamate or AMPA. Subtle, but important differences are found in the ligand-binding cavity between the two AMPA receptor subgroups at position 724 (Tyr in iGluR1/iGluR2 and Phe in iGluR3/iGluR4), which in iGluR4 may lead to displacement of a water molecule and hence points to the possibility to make subgroup specific ligands.
Molecular mechanism of agonist recognition by the ligand-binding core of the ionotropic glutamate receptor 4.,Kasper C, Frydenvang K, Naur P, Gajhede M, Pickering DS, Kastrup JS FEBS Lett. 2008 Dec 10;582(29):4089-94. Epub 2008 Nov 18. PMID:19022251[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Pasternack A, Coleman SK, Fethiere J, Madden DR, LeCaer JP, Rossier J, Pasternack M, Keinanen K. Characterization of the functional role of the N-glycans in the AMPA receptor ligand-binding domain. J Neurochem. 2003 Mar;84(5):1184-92. PMID:12603841
- ↑ Gill A, Birdsey-Benson A, Jones BL, Henderson LP, Madden DR. Correlating AMPA receptor activation and cleft closure across subunits: crystal structures of the GluR4 ligand-binding domain in complex with full and partial agonists. Biochemistry. 2008 Dec 30;47(52):13831-41. PMID:19102704 doi:10.1021/bi8013196
- ↑ Birdsey-Benson A, Gill A, Henderson LP, Madden DR. Enhanced efficacy without further cleft closure: reevaluating twist as a source of agonist efficacy in AMPA receptors. J Neurosci. 2010 Jan 27;30(4):1463-70. PMID:20107073 doi:30/4/1463
- ↑ Kasper C, Frydenvang K, Naur P, Gajhede M, Pickering DS, Kastrup JS. Molecular mechanism of agonist recognition by the ligand-binding core of the ionotropic glutamate receptor 4. FEBS Lett. 2008 Dec 10;582(29):4089-94. Epub 2008 Nov 18. PMID:19022251 doi:S0014-5793(08)00905-8
